none no species Evolution; Parasites diseases and disorders; Parasites; Insect parasites; Hosts; Insect hosts; Host parasite relationships; Habitat; Terrestrial habitat; Land and freshwater zones; Palaearctic region; USSR Chetogena gelida (Tachinidae ); Rogas (Braconidae ); Lepidopteran hosts; Lymantriidae; Parasite adaptation to host life cycle; Host parasite phylogeny; Lymantriidae (Lepidoptera), life cycle, mutual adaptation; Arctic habitat; Tundra; Arctic; Nearctic & USSR; Nearctic region; Russian SFSR; Lepidopteran host mutual life cycle adaptation; Arctic tundra Lymantriidae; Evolutionary adaptation; Life cycle changes; Arctic tundra Nearctic region & Russian SFSR; Dipteran parasites; Chetogena gelida; Hymenopteran parasites; Rogas; Parasite adaptation to life cycle; Nearctic region & Russian SFSR; Host parasite phylogeny; Rogas (Hymenoptera) & Chetogena (Diptera) adaptation to life cycle; Arctic habitat; Tundra; Arctic; Nearctic region; Russian SFSR; Life cycle adaptation & insect parasites; Arctic tundra